Please see Returnees in Global Link to learn how to find returnees in your area as well as Returnee Volunteers trained to work with students interested in studying abroad. A particularly good resource are the Returnee Country Specialists who represent the country in which they studied abroad. They provide future AFSers with insight on living abroad and can talk specifically about the applicant's country of interest.
Also be sure to invite returnees to your Pre-Departure Orientations to share their experiences and real-life tips. They can also talk with participants about the "Returnee Life Cycle" and volunteering opportunities upon program return.